In a large heavy soup pot, heat oil over medium heat. Add onion, carrot and celery. Cook until softened, about 8 minutes. Add chiles, cumin, and oregano, and cook another 2 minutes; season with salt. Add broth, beans, tomato, and corn and bring to a boil. Reduce heat and simmer for 20 minutes. Remove from heat and stir in lime juice and cilantro.